Weight gain from early to middle adulthood may increase chronic disease risk

WASHINGTON, July 18 (Xinhua) -- Weight gain from early adulthood to age 55 may increase the risk of chronic diseases, premature death, and decreased the likelihood of achieving healthy aging, according to a study published Tuesday by the U.S. journal JAMA.

"Our study is the first of its kind to systematically examine the association of weight gain from early to middle adulthood with major health risks later in life," said senior author Frank Hu, professor of nutrition and epidemiology and chair of the Department of Nutrition at the Harvard University.

"The findings indicate that even a modest amount (2.5 to 10 kg) of weight gain may have important health consequences."

Obesity is a major global health challenge. The worldwide prevalence of obesity was 11 percent for men and 15 percent for women in 2014 compared with five percent for men and eight percent for women in 1980.

Among U.S. adults, the average weight gain is 0.5 to 1.0 kg per year from early to middle adulthood and this modest yearly accumulation of weight eventually leads to obesity over time.

However, it is unclear how weight gain during the transition from early to middle adulthood, when most weight gain occurs, relates to subsequent health consequences, such as type 2 diabetes, hypertension and cardiovascular disease.

Hu and colleagues analyzed health data from nearly 120,000 study participants, including women in the Nurses' Health Study between 1976 and 2012, and men in the Health Professionals Follow-Up Study between 1986 and 2012.

Participants were asked to recall their weight from early adulthood, age 18 for women and 21 for men, and to report their weight at age 55.

Women gained an average of 12.6 kg over early to middle adulthood, and men about 9.7 kg.

Compared to those who kept their weight stable, those who gained a moderate amount of weight had an increased risk of major chronic diseases and premature death, and were less likely to score well on a "healthy aging" assessment of physical and cognitive health.

In a meta-analysis of study participants from the two cohorts, each five-kg weight gain was associated with a 30 percent increased risk of type 2 diabetes, 14 percent increased risk of hypertension, eight percent increased risk of cardiovascular disease, six percent increased risk of obesity-related cancer, five percent increased risk of dying prematurely, and 17 percent decreased odds of achieving healthy aging.

"These findings may help counsel patients regarding the risks of weight gain," the researchers wrote.